Abstract

In a wavelength division multiplexed (WDM) optical transmission system, the optical channel add/drop brings out power excursions (or power transients) of surviving optical channels in an erbium-doped fiber amplifier (EDFA).^1,2 These effects are mainly caused by cross gain saturation in erbium-doped fiber. Although these power excursions in transient state are small in a single amplifier, it may grow rapidly in cascaded optical amplifiers and affect a bit error rate and quality of the surviving channels.^3,4 These effects in L-band (1570 1610 nm) EDFA, which has been developed to increase a capacity of optical transmission system,⁵ were demonstrated and were compared with those in C-band (1530 1565 nm) EDFA.^6,7 But, the experimental results of these transient effects in L-band EDFA have never been precisely shown in the whole wavelength of L-band. Here, we report the wavelength dependency of the transient effects in the range of 1570 1600 nm and present how to determine the speed of pump control to maintain the population inversion and consequently suppress the power excursions of surviving channels in L-band EDFA.

© 2002 Optical Society of America